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61.
在花年毛竹纯林进行1a覆盖-1a套种竹荪轮作等经营模式试验,研究毛竹林覆盖后套种竹荪轮作模式经济效益和生态修复作用。结果表明:(1)1 a覆盖-1 a套种竹荪轮作模式的2 a净收入达到18.0万元/hm2,投入产出比达到1∶3.29,分别是传统单一经营模式、1 a覆盖-1 a自然培育经营模式的19.6倍和1.6倍。(2)毛竹林覆盖后套种竹荪轮作模式在高碳氮比(C/N)有机物覆盖的清理、林地土壤改良、林地地力培育等生态修复效果明显优于1 a覆盖-1 a自然培育经营模式,有效防止竹林地因覆盖而引发竹林衰退。毛竹林覆盖与套种竹荪轮作模式是毛竹林可持续性发展的经营模式,可作为毛竹林覆盖的配套经营措施在生产上推广应用。 相似文献
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Raissa Rachel Salustriano da Silva-Matos Gabriel Barbosa da Silva Jr Adenaelson de Souza Marques Maciel Lima Monteiro Josy Anteveli Osajima 《Archives of Agronomy and Soil Science》2016,62(3):445-455
The identification of alternative substrates suitable for seedling production is very important, while boron nutrition is also relevant due to plant requirement and its difficult management. Thus, four experiments were carried out from October 2012 to April 2013 to evaluate the effect of substrates using decomposed buriti (Mauritia vinifera Mart.) stem (DBS) and boron fertilizing for seedling production of yellow passion fruit (Passiflora edulis Sims). The experimental design was completely randomized in factorial scheme 6 × 2 + 1, referring to the substrates [S1: DBS, S2: soil and sand 1:1 (20%) + DBS (80%), S3: soil and sand 1:1 (40%) + DBS (60%), S4: soil and sand 1:1 (60%) + DBS (40%), S5: soil and sand 1:1 (80%) + DBS (20%), S6: commercial substrate (additional treatment) and S7: soil, sand and manure 1:1:2] with and without boron. The seedling emergence, emergence rate, plant height, stem diameter, root length, root volume and dry mass of roots and shoots were recorded. The substrates S2 (without B fertilizing) and S4 (B fertilized with 0.5 mg dm?3) produced seedlings with more than 3.0 g of shoot dry mass and at least 30 cm in height, and can be used for production of high-quality yellow passion fruit seedlings. 相似文献
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西番莲愈伤组织诱导研究 总被引:2,自引:0,他引:2
以紫果西番莲的花蕾为材料,进行组织培养愈伤组织诱导的研究.结果表明:直接剥取子房可快速有效诱导愈伤组织产生,在MS+2,4-D2.0+KT2.0培养基中,愈伤细织诱导率为90%,在MS+2,4-D0.5中培养,愈伤组织增殖倍数为8.98。 相似文献
66.
厚壁毛竹(Phyllostachys edulis'Pachyloen')亦名厚皮毛竹,与毛竹(Phyllostachys eduli s(Carr.)H.de Lehaie)相似,但竿略呈四方形,因竿壁厚而与毛竹不同~([1]).厚壁毛竹是一个材、笋兼优的毛竹变异类型,江西特有,仅零星分布于万载、宜丰、铜鼓三县~([2]).目前,野生状态的厚壁毛竹种群数量少,处于濒危状态,已被列为江西省重点保护植物~([1]). 相似文献
67.
光慈姑主要成分分析测定 总被引:2,自引:0,他引:2
采用高效液相、碘显色法和苯酚-浓硫酸显色法,对光慈姑的秋水仙碱、淀粉和多糖的含量进行了分析测定;并对多糖提取条件进行了初步探讨.实验结果表明,在562nm波长下,线性方程为:y=0.00807x+0.00713,r=0.99945(n=10);平均回收率=99.36%,淀粉含量0.2753g/g.在489nm波长下,线性方程为y=0.01048x-0.02186,r=0.99905(n=9),平均回收率为98.67%,多糖含量0.1134g/g.在350nm波长下,线性方程为y=8959.47951x-20001.65556,r=0.99737(n=9),平均回收率为98.12%,秋水仙碱含量0.0754 g/g.采用95%乙醇进行沉淀,多糖的含量较高. 相似文献
68.
Bela H. Buck Michael W. Ebeling Tanja Michler-Cieluch 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):255-281
More than 50% of the annual worldwide harvest of mussels is produced in Europe. The mussel cultivation in Germany is based on an extensive on-bottom culture and depends entirely on natural resources for food, spat and space. Due to stakeholder conflicts and a lack of spat availability, mussel farmers tend to move offshore where space is not limited and adequate settlement guaranteed. Newcomers – the offshore wind farmers – are covering large areas in the German Bight which in contrast give the opportunity to use these areas in a multifunctional way by accepting mussel cultivation within the wind farms. This study compiles the basic data for offshore mussel cultivation in close vicinity to a designated offshore wind farm in the open sea of the German Bight and employs different case-scenario calculations to illustrate the impact of changing parameter values on overall profitability or non-profitability of this activity. Primary focus is placed on the production of consumer mussels but seed mussel cultivation is also taken into consideration. We show that production of consumer mussels with longline technology is sufficiently profitable even under the assumption of substantial cost increases. This is especially true, if existing capacities could be used. The cultivation of seed mussels depends on the possibility of using existing equipment. A substantial increase of seed mussel prices to at least 0.6 €, given the main cost categories remaining constant, turns this alternative into substantial profitability. This study concludes with providing some recommendations on how favorable terms or actions could further improve profitability of offshore mussel cultivation. Altogether, our results are intended to shed some light on business management topics that future offshore mariculture operators such as traditional mussel farmers should follow in order to be efficient. 相似文献
69.
对雷竹秋季覆盖、冬季覆盖和普通栽培以及毛竹林大量施肥和基本不施肥等不同栽培方式的竹笋亚硝酸盐残留量进行分析研究。结果表明,雷竹笋亚硝酸盐的残留量从高到低排列为冬季覆盖笋 > 普通栽培笋 > 秋季覆盖笋;毛竹林中低产林的鞭笋和冬笋的亚硝酸盐残留量都比高产林要多;土壤中的氮含量和土壤温度可能影响竹笋亚硝酸盐的残留量。 相似文献
70.
不同施肥处理对毛竹根际微生物影响及其PCR-DGGE分析 总被引:2,自引:0,他引:2
采用PCR-DGGE技术对不同施肥处理毛竹根际微生物多样性特征进行研究.结果表明:采用改进的蛋白酶K-CTAB法提取的毛竹土壤DNA经PCR扩增的产物经DGGE检测后得到的电泳条带清晰且分离效果好,可以明显反映出毛竹根际微生物多样性的变化.根际微生物种群组成特征受施肥量、肥料种类影响很大,施肥能够增加毛竹根际微生物的多... 相似文献